Publications

comparative study of the prevalence of intestinal parasites in low socioeconomic areas from south chennai, india.	intestinal parasites cause one of the most important health problems through their effects in causing undernourishment morbidity and incapacitation due to their behavior particularly in children compared to adults. this study was intended to state the prevalence of intestinal parasites between the slum dwellers of different areas in south chennai. among the total of 256 samples collected between the ages of 0-50 yrs, 194 samples were positive. standard laboratory techniques for parasitological d ...	2014	24587897
entamoeba bangladeshi: an insight.	molecular tools have the potential to differentiate microscopically similar gut micro-eukaryotes that may have significantly different relationships with the human host. using broad range entamoeba primers to amplify a section of the eukaryotic 18s small subunit ribosomal rna gene a novel member of the entamoeba family (entamoeba bangladeshi) has recently been identified. the goal of this review is to place this species in the context of what is already known about this genus and to discuss the ...	2014	25250229
laboratory methods of identification of entamoeba histolytica and its differentiation from look-alike entamoeba spp.	entamoeba histolytica, the causative agent of intestinal and extraintestinal amebiasis, is a common parasitic cause of significant morbidity and mortality in the developing countries. hence, early detection and differentiation of pathogenic e. histolytica from nonpathogenic/commensal entamoeba spp (entamoeba dispar/entamoeba moshkovskii/entamoeba bangladeshi) plays a crucial role in clinical management of patients with amebiasis. most diagnostic tests currently available do not reliably differen ...	2014	25250228
discrimination of entamoeba spp. in children with dysentery.	the present study was performed in order to differentiate e. histolytica and e. dispar in children from gorgan city, using a pcr method.	2014	25120897
erythrophagocytosis in entamoeba histolytica and entamoeba dispar: a comparative study.	entamoeba histolytica is the causative agent of human intestinal and liver amebiasis. the extraordinary phagocytic activity of e. histolytica trophozoites has been accepted as one of the virulence mechanisms responsible for their invasive capacity. the recognition of the noninvasive entamoeba dispar as a different species has raised the question as to whether the lack of pathogenic potential of this ameba correlates with a limited phagocytic capacity. we have therefore compared the process of er ...	2014	25003123
entamoeba dispar: a rare case of enteritis in a patient living in a nonendemic area.	entamoeba dispar, a common noninvasive parasite, is indistinguishable in its cysts and trophozoite forms from entamoeba histolytica, the cause of invasive amebiasis, by microscopy. to differentiate the two species seems to be a problem for laboratory diagnosis. recent experimental studies showed that e. dispar can be considered pathogenic too. we present a rare case of enteritis due to e. dispar.	2014	24851190
frequency of amoebiasis and other intestinal parasitoses in a settlement in ilhéus city, state of bahia, brazil.	this study evaluated the frequency of intestinal parasites, emphasizing the identification and differentiation of entamoeba spp.	2014	24553799
[comparison of direct microscopy, culture, elisa and molecular methods for diagnosis of entamoeba histolytica].	amebiasis, a parasitic infection caused by entamoeba histolytica, is one of the most common parasitic infections worldwide. since it is still an important public health problem in developing countries, rapid differential diagnosis of amebiasis is crucial in terms of treatment. the most frequently used method for laboratory diagnosis is direct microscopy, however more reliable and specific methods are needed in order to differentiate the apathogenic entamoeba dispar under the microscope. this stu ...	2014	24506721
correlation between genotypes of trna-linked short tandem repeats in entamoeba nuttalli isolates and the geographical distribution of host rhesus macaques.	several polymorphic markers, including serine-rich protein genes, have been used for the genotyping of isolates from the morphologically indistinguishable protozoan parasites entamoeba histolytica, entamoeba dispar, and entamoeba nuttalli. genotypes of trna-linked short tandem repeats (strs) are highly polymorphic, but the correlation with geographical distribution is unknown. we have recently isolated 15 e. nuttalli strains from wild rhesus macaques in four locations in kathmandu valley, nepal. ...	2014	24185530
differential diagnosis of entamoeba spp. in clinical stool samples using sybr green real-time polymerase chain reaction.	amoebiasis, a disease caused by entamoeba histolytica, is usually diagnosed by microscopic examination, which does not differentiate the morphologically identical species of the e. histolytica/e. dispar complex. furthermore, morphologically similar species such as entamoeba hartmanni contribute to misidentification. therefore, there is a need for more sensitive and specific methods. this study standardized a multiplex real-time pcr system for e. histolytica and e. dispar and a single real-time p ...	2014	24693242
data set for the proteomics analysis of the endomembrane system from the unicellular entamoeba histolytica.	entamoeba histolytica is the protozoan parasite agent of amebiasis, an infectious disease of the human intestine and liver. this parasite contact and kills human cells by an active process involving pathogenic factors. cellular traffic and secretion activities are poorly characterized in e. histolytica. in this work, we took advantage of a wide proteomic analysis to search for principal components of the endomembrane system in e. histolytica. a total of 5683 peptides matching with 1531 proteins ...	2014	26217682
therapy of liver abscesses.	liver abscess (la) is an uncommon but potentially life-threatening disease with significant morbidity and mortality.	2014	26287275
prevalence of intestinal parasites among the population of the gaza strip, palestine.	intestinal parasitic diseases in gaza strip are a significant health problem. the main aim of this study is to determine the prevalence of parasitic infection among patients in the five governorates of the gaza strip. a cross-sectional parasitological survey was conducted on 600 patients. stool specimens were examined microscopically for the presence of parasite eggs or larvae/cysts per wet amount by the saline iodine and formol-ether concentration method. of 600 subjects examined, 245 (40.8%) w ...	2014	25706427
antiprotozoal activity against entamoeba histolytica of plants used in northeast mexican traditional medicine. bioactive compounds from lippia graveolens and ruta chalepensis.	amoebiasis caused by entamoeba histolytica is associated with high morbidity and mortality is becoming a major public health problem worldwide, especially in developing countries. because of the side-effects and the resistance that pathogenic protozoa build against the standard antiparasitic drugs, e.g., metronidazole, much recent attention has been paid to plants used in traditional medicine around the world in order to find new antiprotozoal agents. we collected 32 plants used in northeast mex ...	2014	25517343
leptin receptor mutation results in defective neutrophil recruitment to the colon during entamoeba histolytica infection.	amebiasis is an enteric infection caused by entamoeba histolytica, with symptoms ranging in severity from asymptomatic colonization to dysentery. humans with the q223r leptin receptor mutation have increased susceptibility to amebiasis, but the mechanism has been unclear. using a mouse model expressing the mutation, we tested the impact of the q223r mutation on the innate immune response to e. histolytica infection. the 223r mutation resulted in delayed clearance of amebae from the cecum, as had ...	2014	25516614
evolutionary genomics and population structure of entamoeba histolytica.	amoebiasis caused by the gastrointestinal parasite entamoeba histolytica has diverse disease outcomes. study of genome and evolution of this fascinating parasite will help us to understand the basis of its virulence and explain why, when and how it causes diseases. in this review, we have summarized current knowledge regarding evolutionary genomics of e. histolytica and discussed their association with parasite phenotypes and its differential pathogenic behavior. how genetic diversity reveals pa ...	2014	25505504
crystal structure of calcium binding protein-5 from entamoeba histolytica and its involvement in initiation of phagocytosis of human erythrocytes.	entamoeba histolytica is the etiological agent of human amoebic colitis and liver abscess, and causes a high level of morbidity and mortality worldwide, particularly in developing countries. there are a number of studies that have shown a crucial role for ca2+ and its binding protein in amoebic biology. ehcabp5 is one of the ef hand calcium-binding proteins of e. histolytica. we have determined the crystal structure of ehcabp5 at 1.9 å resolution in the ca2+-bound state, which shows an unconvent ...	2014	25502654
regulation of serum-responsive transmembrane kinase ehtmkb1-9 by an unsaturated lipid, oleic acid in protistan parasite entamoeba histolytica.	transmembrane kinases of entamoeba histolytica are known to play a wide range of roles from virulence, phagocytosis, and proliferation to stress response. transmembrane kinase ehtmkb1-9 is thought to be involved in early proliferative response and it was originally identified as a serum inducible gene. ability to stimulate ehtmkb1 expression of serum starved cells resides in unsaturated fatty acids associated with albumin fraction of serum and the mechanism of stimulation follows activation of e ...	2014	25497959
amebiasis presenting as acute appendicitis: report of a case and review of japanese literature.	outside of these high-risk regions, acute amebic appendicitis is considerably rarer and the mortality rate is much higher than with non-amebic appendicitis.	2014	25460473
crystal structures of entamoeba histolytica lysyl-trna synthetase reveal conformational changes upon lysine binding and a specific helix bundle domain.	the class ii lysyl-trna synthetases (krs) are conserved aminoacyl-trna synthetases that attach lysine to the cognate trna in a two-step mechanism. the enzyme from the parasitic protozoan entamoeba histolytica was crystallized in the presence of small ligands to generate snapshots of the lysine-adenylate formation. the residues involved in lysine activation are highly conserved and the active site closes around the lysyl-adenylate, as observed in bacterial krs. the entamoeba emapii-like polypepti ...	2014	25448989
immune markers characteristic for asymptomatically infected and diseased entamoeba histolytica individuals and their relation to sex.	the protozoan parasite entamoeba histolytica (e. histolytica) usually asymptomatically colonizes the human intestine. in the minority of the cases, the parasite evades from the gut and can induce severe symptoms like colitis or amebic liver abscess (ala). interestingly, ala predominates in adult men despite a higher prevalence of the parasite in women. the present study aimed to identify characteristic serum markers in a unique cohort of clearly defined asymptomatically infected e. histolytica i ...	2014	25420932
differentially expressed genes of virulent and nonvirulent entamoeba histolytica strains identified by suppression subtractive hybridization.	entamoeba histolytica is a parasite which presents capacity to degrade tissues and therefore has a pathogenic behavior. as this behavior is not shown by all strains, there have been several studies investigating molecular basis of the cytotoxicity process. using the suppression subtractive hybridization (ssh) technique, differential gene expressions of two e. histolytica strains, one virulent (egg) and one nonvirulent (452), have been analyzed with the purpose of isolating genes which may be inv ...	2014	25313356
[analysis of intestinal ameobiasis in patients with diarrhea by adhesin antigen test and direct microscopy].	in this study, we aimed to research the frequency of intestinal amebiasis in patients who applied with diarrhea retrospectively for a year and compare direct microscopic analysis and elisa adhesin antigen test for entamoeba histolytica procedures.	2014	25308451
biochemical and kinetic characterization of the recombinant adp-forming acetyl coenzyme a synthetase from the amitochondriate protozoan entamoeba histolytica.	entamoeba histolytica, an amitochondriate protozoan parasite that relies on glycolysis as a key pathway for atp generation, has developed a unique extended ppi-dependent glycolytic pathway in which adp-forming acetyl-coenzyme a (coa) synthetase (acd; acetate:coa ligase [adp-forming]; ec 6.2.1.13) converts acetyl-coa to acetate to produce additional atp and recycle coa. we characterized the recombinant e. histolytica acd and found that the enzyme is bidirectional, allowing it to potentially play ...	2014	25303954
a novel alpha kinase ehak1 phosphorylates actin and regulates phagocytosis in entamoeba histolytica.	phagocytosis plays a key role in nutrient uptake and virulence of the protist parasite entamoeba histolytica. phagosomes have been characterized by proteomics, and their maturation in the cells has been studied. however, there is so far not much understanding about initiation of phagocytosis and formation of phagosomes at the molecular level. our group has been studying initiation of phagocytosis and formation of phagosomes in e. histolytica, and have described some of the molecules that play ke ...	2014	25299184
crystal structures and kinetics of type iii 3-phosphoglycerate dehydrogenase reveal catalysis by lysine.	d-phosphoglycerate dehydrogenase (pgdh) catalyzes the first committed step of the phosphorylated serine biosynthesis pathway. here, we report for the first time, the crystal structures of type iiik pgdh from entamoeba histolytica in the apo form, as well as in complexes with substrate (3-phosphoglyceric acid) and cofactor (nad(+) ) to 2.45, 1.8 and 2.2 å resolution, respectively. comparison of the apo structure with the substrate-bound structure shows that the substrate-binding domain is rotated ...	2014	25294608
the parasite entamoeba histolytica exploits the activities of human matrix metalloproteinases to invade colonic tissue.	intestinal invasion by the protozoan parasite entamoeba histolytica is characterized by remodelling of the extracellular matrix (ecm). the parasite cysteine proteinase a5 (cp-a5) is thought to cooperate with human matrix metalloproteinases (mmps) involved in ecm degradation. here, we investigate the role cp-a5 plays in the regulation of mmps upon mucosal invasion. we use human colon explants to determine whether cp-a5 activates human mmps. inhibition of the mmps' proteolytic activities abolishes ...	2014	25291063
interaction between nbp35 and cfd1 proteins of cytosolic fe-s cluster assembly reveals a stable complex formation in entamoeba histolytica.	iron-sulfur (fe-s) proteins are involved in many biological functions such as electron transport, photosynthesis, regulation of gene expression and enzymatic activities. biosynthesis and transfer of fe-s clusters depend on fe-s clusters assembly processes such as isc, suf, nif, and cia systems. unlike other eukaryotes which possess isc and cia systems, amitochondriate entamoeba histolytica has retained nif & cia systems for fe-s cluster assembly in the cytosol. in the present study, we have eluc ...	2014	25271645
microscopy versus enzyme linked immunosorbent assay test for detection of entamoeba histolytica infection in stool samples.		2014	25250240
amoeboma of colon mimicking colonic carcinoma.	entamoeba histolytica is a major cause of diarrhea in the developing countries and it can present with a wide range of gastrointestinal symptoms depending on the phase of the infection. we describe a case of 65-year-old male patient presented with abdominal pain and vomiting. on the clinical and radiological examination provisional diagnosis of colonic carcinoma was suspected. after resection of perforated caecal growth, histopathological sections showed numerous trophozoites of e. histolytica i ...	2014	25250235
neglected tropical diseases among two indigenous subtribes in peninsular malaysia: highlighting differences and co-infection of helminthiasis and sarcocystosis.	soil-transmitted helminth (sth) infections have been documented among these minority groups since 1938. however the prevalence of sth is still high among these communities. most studies tend to consider the orang asli (indigenous) as a homogenous group. in contrary, different subtribes have their own cultural practices. to understand this variation better, we studied the prevalence and associated factors of sth and other gut parasitic infections among two common subtribes (i.e. temuan and temiar ...	2014	25248116
the mak16 gene of entamoeba histolytica and its identification in isolates from patients.	to identify sequences of entamoeba histolytica associated with the development of amebic liver abscess (ala) in hamsters, subtractive hybridization of cdna from e. histolytica hm-1:imss under 2 growth conditions was performed: 1) cultured in axenic medium and 2) isolated from experimental ala in hamsters. for this procedure, 6 sequences were obtained. of these sequences, the mak16 gene was selected for amplification in 29 cultures of e. histolytica isolated from the feces of 10 patients with int ...	2014	25246723
amoebic pi3k and pkc is required for jurkat t cell death induced by entamoeba histolytica.	the enteric protozoan parasite entamoeba histolytica is the causative agent of human amebiasis. during infection, adherence of e. histolytica through gal/galnac lectin on the surface of the amoeba can induce caspase-3-dependent or -independent host cell death. phosphorylinositol 3-kinase (pi3k) and protein kinase c (pkc) in e. histolytica play an important function in the adhesion, killing, or phagocytosis of target cells. in this study, we examined the role of amoebic pi3k and pkc in amoeba-ind ...	2014	25246714
identification of phosphatidylcholine transfer protein-like in the parasite entamoeba histolytica.	caveolin is the protein marker of caveola-mediated endocytosis. previously, we demonstrated by immunoblotting and immunofluorescence that an anti-chick embryo caveolin-1 monoclonal antibody (mab) recognizes a protein in amoeba extracts. nevertheless, the caveolin-1 gene is absent in the entamoeba histolytica genome database. in this work, the goal was to isolate, identify and characterize the protein that cross-reacts with chick embryo caveolin-1. we identified the protein using a proteomic appr ...	2014	25223890
a new human 3d-liver model unravels the role of galectins in liver infection by the parasite entamoeba histolytica.	investigations of human parasitic diseases depend on the availability of appropriate in vivo animal models and ex vivo experimental systems, and are particularly difficult for pathogens whose exclusive natural hosts are humans, such as entamoeba histolytica, the protozoan parasite responsible for amoebiasis. this common infectious human disease affects the intestine and liver. in the liver sinusoids e. histolytica crosses the endothelium and penetrates into the parenchyma, with the concomitant i ...	2014	25211477
gene expression profiling in entamoeba histolytica identifies key components in iron uptake and metabolism.	entamoeba histolytica is an ameboid parasite that causes colonic dysentery and liver abscesses in humans. the parasite encounters dramatic changes in iron concentration during its invasion of the host, with relatively low levels in the intestinal lumen and then relatively high levels in the blood and liver. the liver notably contains sources of iron; therefore, the parasite's ability to use these sources might be relevant to its survival in the liver and thus the pathogenesis of liver abscesses. ...	2014	25210888
ehcoactosin stabilizes actin filaments in the protist parasite entamoeba histolytica.	entamoeba histolytica is a protist parasite that is the causative agent of amoebiasis, and is a highly motile organism. the motility is essential for its survival and pathogenesis, and a dynamic actin cytoskeleton is required for this process. ehcoactosin, an actin-binding protein of the adf/cofilin family, participates in actin dynamics, and here we report our studies of this protein using both structural and functional approaches. the x-ray crystal structure of ehcoactosin resembles that of hu ...	2014	25210743
immunity in urogenital protozoa.	innate and adaptive immunity play a significant role in urogenital infections. innate immunity is provided by the epithelial cells and mucus lining along with acidic ph, which forms a strong physical barrier against the pathogens in female reproductive tract. cells of innate immune system, antimicrobial peptides, cytokines, chemokines and adaptive immunity in the reproductive tract are evolved during infection, and a pro-inflammatory response is generated to fight against the invading pathogen t ...	2014	25201404
rnai pathway genes are resistant to small rna mediated gene silencing in the protozoan parasite entamoeba histolytica.	the rna interference pathway in the protist entamoeba histolytica plays important roles in permanent gene silencing as well as in the regulation of virulence determinants. recently, a novel rna interference (rnai)-based silencing technique was developed in this parasite that uses a gene endogenously silenced by small rnas as a "trigger" to induce silencing of other genes that are fused to it. fusion to a trigger gene induces the production of gene-specific antisense small rnas, resulting in robu ...	2014	25198343
discovery of entamoeba histolytica hexokinase 1 inhibitors through homology modeling and virtual screening.	entamoeba histolytica, the parasite which causes amebiasis is responsible for 110,000 deaths a year. entamoeba histolytica depends on glycolysis to obtain atp for cellular work. according to metabolic flux studies, hexokinase exerts the highest flux control of this metabolic pathway; therefore, it is an excellent target in the search of new antiamebic drugs. to this end, a tridimensional model of e. histolytica hexokinase 1 (ehhk1) was constructed and validated by homology modeling. after virtua ...	2014	23534932
expression, purification, and evaluation of recombinant leca as a candidate for an amebic colitis vaccine.	entamoeba histolytica, which causes amebic colitis and liver abscess, is considered a major enteric pathogen in residents and travelers to developing countries where the disease is endemic. interaction of this protozoan parasite with the intestine is mediated through the binding of the trophozoite stage to intestinal mucin and epithelium via a galactose and n-acetyl-d-galactosamine (gal/galnac) lectin comprised of a disulfide linked heavy (ca. 180 kda) and light chain (ca. 35 kda) and a noncoval ...	2014	23827311
the ribosomal rna transcription unit of entamoeba invadens: accumulation of unprocessed pre-rrna and a long non coding rna during encystation.	the ribosomal rna genes in entamoeba spp. are located on extrachromosomal circular molecules. unlike model organisms where rrna transcription stops during growth stress, entamoeba histolytica continues transcription; but unprocessed pre-rrna accumulates during stress, along with a novel class of circular transcripts from the 5'-external transcribed spacer (ets). to determine the fate of rrna transcription during stage conversion between trophozoite to cyst we analyzed entamoeba invadens, a model ...	2014	24200639
multilocus sequence typing system (mlst) reveals a significant association of entamoeba histolytica genetic patterns with disease outcome.	the relationship between parasite genotypes and outcome of amoebic infection is still a paradox and needed to be explored. proper identification and genetic characterization of entamoeba histolytica clinical isolates is an effective tool for exploring this relation. along with conventional polymorphic marker (chitinase), trna linked short tandem repeat (str) loci has been employed as multilocus genotyping tool due to its better resolution and evolutionary significance. some common as well as exc ...	2014	24321887
gal-lectin-dependent contact activates the inflammasome by invasive entamoeba histolytica.	entamoeba histolytica (eh) is an extracellular protozoan parasite of the human colon, which occasionally breaches the intestinal barrier. eradicating ameba that invades is essential for host survival. a defining but uncharacterized feature of amebic invasion is direct contact between ameba and host cells. this event corresponds with a massive pro-inflammatory response. to date, pathogen recognition receptors (prrs) that are activated by contact with viable eh are unknown. here we show that the i ...	2014	24253103
deciphering molecular mechanisms of mrna metabolism in the deep-branching eukaryote entamoeba histolytica.	although extraordinary rapid advance has been made in the knowledge of mechanisms regulating messenger rna (mrna) metabolism in mammals and yeast, little information is known in deep-branching eukaryotes. the complete genome sequence of entamoeba histolytica, the protozoan parasite responsible for human amoebiasis, provided a lot of information for the identification and comparison of regulatory sequences and proteins potentially involved in mrna synthesis, processing, and degradation. here, we ...	2014	24249245
rickettsiae, protozoa, and opisthokonta/metazoa.	rhizobiales (formerly named rickettsiales) cause in rare instances meningitis and meningovasculitis, respectively. in case of history of exposure, infection by rhizobiales needs to be considered since both diagnosis and therapy may be extremely difficult and pathogen-specific. the same applies to protozoa; in this chapter, babesia species, free-living amoebae and entamoeba histolytica infection, including severe meningitis and brain abscess, infection by trypanosoma species (south american and a ...	2014	24365428
evaluation of the effect of miltefosine on trichomonas vaginalis.	trichomonas vaginalis causes trichomoniasis in humans, a sexually transmitted disease commonly treated with metronidazole (mtz). mtz is known to cause undesirable side effects, and mtz-resistant parasites have been reported. thus, the development of an alternative treatment is desirable. miltefosine (mlt) is an alkylphosphocholine synthetic lipid analogue that displays antiparasitic activity against leishmania, trypanosoma cruzi, entamoeba histolytica, acanthamoeba spp., giardia lamblia, t. vagi ...	2014	24363204
clinical significance of high anti-entamoeba histolytica antibody titer in asymptomatic hiv-1-infected individuals.	anti-entamoeba histolytica antibody (anti- e. histolytica) is widely used in seroprevalence studies though its clinical significance has not been assessed previously.	2014	24338349
entamoeba histolytica acetyl-coa synthetase: biomarker of acute amoebic liver abscess.	to characterize the entamoeba histolytica (e. histolytica) antigen(s) recognized by moribound amoebic liver abscess hamsters.	2014	25182945
the macrophage migration inhibitory factor homolog of entamoeba histolytica binds to and immunomodulates host macrophages.	the host inflammatory response contributes to the tissue damage that occurs during amebic colitis, with tumor necrosis factor alpha (tnf-α) being a key mediator of the gut inflammation observed. mammalian macrophage migration inhibitory factor (mif) is a proinflammatory cytokine that plays an important role in the exacerbation of a wide range of inflammatory diseases, including colitis. we identified a mif gene homolog in the entamoeba histolytica genome, raising the question of whether e. histo ...	2014	24818664
conformational changes induced by detergents during the refolding of chemically denatured cysteine protease ppehcp-b9 from entamoeba histolytica.	ehcp-b9, a cysteine protease (cp) involved in entamoeba histolytica virulence, is a potential target for disease diagnosis and drug design. after purification from inclusion bodies produced in escherichia coli, the recombinant ehcp-b9 precursor (ppehcp-b9) can be refolded using detergents as artificial chaperones. however, the conformational changes that occur during ppehcp-b9 refolding remain unknown. here, we comprehensively describe conformational changes of ppehcp-b9 that are induced by vari ...	2014	24769005
new evidence of entamoeba histolytica infections in pre-columbian and colonial cemeteries in the caribbean.	elisa was used to test the presence of the human pathogenic amoeba entamoeba histolytica in archaeological samples from 2 cemeteries in guadeloupe, in the caribbean. results show that 15.9% of the population was infected during the colonial period, a value comparable to the current rates observed in humans in adjacent countries. this study also confirms the presence of the current strain of e. histolytica in pre-columbian south america before the european colonization in the 15th century and rai ...	2014	24766261
analysis of u3 snorna and small subunit processome components in the parasitic protist entamoeba histolytica.	in the early branching parasitic protist entamoeba histolytica, pre-rrna synthesis continues when cells are subjected to growth stress, but processing slows down and unprocessed pre-rrna accumulates. to gain insight into the regulatory mechanisms leading to accumulation, it is necessary to define the pre-rrna processing machinery in e. histolytica. we searched the e. histolytica genome sequence for homologs of the ssu processome, which contains the u3snorna, and 72 proteins in yeast. we could id ...	2014	24631428
proteomic identification of s-nitrosylated proteins in the parasite entamoeba histolytica by resin-assisted capture: insights into the regulation of the gal/galnac lectin by nitric oxide.	entamoeba histolytica is a gastrointestinal protozoan parasite that causes amebiasis, a disease which has a worldwide distribution with substantial morbidity and mortality. nitrosative stress, which is generated by innate immune cells, is one of the various environmental challenges that e. histolytica encounters during its life cycle. although the effects of nitric oxide (no) on the regulation of gene expression in this parasite have been previously investigated, our knowledge on s-nitrosylated ...	2014	24626316
post-travel screening of asymptomatic long-term travelers to the tropics for intestinal parasites using molecular diagnostics.	the incidence of asymptomatic travel-related parasitic infection is uncertain. previous studies did not distinguish new incident infections, from past infections. regardless of symptoms, we performed multiplex real-time polymerase chain reaction on pre- and post-travel stool samples of dutch long-term travelers to the (sub)tropics. serological screening for schistosoma spp. was only performed in travelers to sub-saharan africa. in total, 679 travelers were included in the study. the follow-up ra ...	2014	24615130
entamoeba histolytica: gene expression analysis of cells invading tissues.	entamoeba histolytica is a protozoan parasite that presents a risk to the health of millions of people worldwide. due to the existence of different clinical forms caused by the parasite and also different virulence levels presented by one strain, one would expect differences in the profile of gene transcripts between virulent and nonvirulent cultures. in this study we used the differential display to select gene segments related to invasiveness of amoeba. one brazilian strain of e. histolytica i ...	2014	24605052
laboratory diagnosis of amebiasis in a sample of students from southeastern brazil and a comparison of microscopy with enzyme-linked immunosorbent assay for screening of infections with entamoeba sp.	epidemiological studies on amebiasis have been reassessed since entamoeba histolytica and e. dispar were first recognized as distinct species. because the morphological similarity of these species renders microscopic diagnosis unreliable, additional tools are required to discriminate between entamoeba species. the objectives of our study were to compare microscopy with elisa kit (ivd®) results, to diagnose e. histolytica infection, and to determine the prevalence of amebiasis in a sample of stud ...	2014	24603737
the entamoeba histolytica dnmt2 homolog (ehmeth) confers resistance to nitrosative stress.	nitric oxide (no) has antimicrobial properties against many pathogens due to its reactivity as an s-nitrosylating agent. it inhibits many of the key enzymes that are involved in the metabolism and virulence of the parasite entamoeba histolytica through s-nitrosylation of essential cysteine residues. very little information is available on the mechanism of resistance to no by pathogens in general and by this parasite in particular. here, we report that exposure of the parasites to s-nitrosoglutat ...	2014	24562908
risk factors for intestinal parasitosis among antiretroviral-treated hiv/aids patients in ethiopia.	summary a cross-sectional survey was conducted to determine the risk factors associated with intestinal parasitosis in hiv/aids patients receiving antiretroviral therapy (art). socio-demographic information was collected and faecal samples were analysed from 384 randomly selected patients on art. data on cd4+ t-cell counts and world health organization clinical staging were obtained from the medical records at the hospital. the overall prevalence of intestinal parasitosis was 56% (95% confidence ...	2014	24554001
unusual multiple large abscesses of the liver: interest of the radiological features and the real-time pcr to distinguish between bacterial and amebic etiologies.	we report a rare case of amebiasis generating 19 large liver abscesses. such a quantity of abscesses is rare, especially when occurring in a young casual traveler without any immunodeficiency disorders. a possible co-infection was excluded. by contrast, the amebic etiology was confirmed by means of serology and real-time pcr.	2014	24548161
expression of ehrad54, ehrad51, and ehblm proteins during dna repair by homologous recombination in entamoeba histolytica.	entamoeba histolytica, the protozoan responsible for human amoebiasis, exhibits a great genome plasticity that is probably related to homologous recombination events. it contains the rad52 epistasis group genes, including ehrad51 and ehrad54, and the ehblm gene, which are key homologous recombination factors in other organisms. ehrad51 and ehrad54 genes are differentially transcribed in trophozoites when dna double-strand breaks are induced by ultraviolet-c irradiation. moreover, the ehrad51 rec ...	2014	24534563
synthesis of 4'-(2-ferrocenyl)-2,2':6'2''-terpyridine: characterization and antiprotozoal activity of mn(ii), co(ii), ni(ii), cu(ii) and zn(ii) complexes.	a terpyridine ligand fctpy was reacted with divalent metals (cu, co, mn, ni and zn), yielding five complexes of general formula [metal(fctpy)2][pf6]2. the structure of fctpy was determined by single crystal x-ray diffraction studies. the complexes characterized using various spectroscopic techniques suggested an octahedral geometry around the central metal ion. these complexes were screened for their antiamoebic, trypanocidal and antimalarial activities. it was found that, complexes 2 and 3 show ...	2014	24534536
design, synthesis and biological evaluation of 3-[4-(7-chloro-quinolin-4-yl)-piperazin-1-yl]-propionic acid hydrazones as antiprotozoal agents.	n-acylhydrazones derived from 7-chloro-4-piperazin-1-yl-quinoline were synthesized and biologically evaluated for blood-stage of plasmodium falciparum and entamoeba histolytica trophozoites. n-acylhydrazone f12 was found to inhibit the p. falciparum growth as well as its life cycle with good selectivity, which was achieved by inhibiting hematin formation. compound f24 showed better ic50 value than the amoebicidal drug metronidazole.	2014	24530492
the future for vaccine development against entamoeba histolytica.	entamoeba histolytica is the causative agent of amebiasis, one of the top three parasitic causes of mortality worldwide. in the majority of infected individuals, e. histolytica asymptomatically colonizes the large intestine, while in others, the parasite breaches the mucosal epithelial barrier to cause amebic colitis and can disseminate to soft organs to cause abscesses. vaccinations using native and recombinant forms of the parasite gal-lectin have been successful in protecting animals against ...	2014	24504133
entamoeba histolytica-secreted cysteine proteases induce il-8 production in human mast cells via a par2-independent mechanism.	entamoeba histolytica is an extracellular tissue parasite causing colitis and occasional liver abscess in humans. e. histolytica-derived secretory products (sps) contain large amounts of cysteine proteases (cps), one of the important amoebic virulence factors. although tissue-residing mast cells play an important role in the mucosal inflammatory response to this pathogen, it is not known whether the sps induce mast cell activation. in this study, when human mast cells (hmc-1 cells) were stimulat ...	2014	24502918
structure, absolute configuration, and antidiarrheal activity of a thymol derivative from ageratina cylindrica.	the leaves of ageratina cylindrica afforded a thymol derivative that was characterized by physical and spectroscopical methods as (8s)-8,9-epoxy-6-hydroxy-l0-benzoyloxy-7-oxothymol isobutyrate (1). the absolute configuration of 1 was established as 8s by vibrational circular dichroism spectroscopy in combination with density functional theory calculations and by evaluation of the flack and hooft x-ray parameters. compound 1 showed weak antiprotozoal activity against entamoeba histolytica and gia ...	2014	24502360
association between allelic variation due to short tandem repeats in trna gene of entamoeba histolytica and clinical phenotypes of amoebiasis.	genotypes of entamoeba histolytica (e. histolytica) may contribute clinical phenotypes of amoebiasis such as amoebic liver abscess (ala), dysentery and asymptomatic cyst passers state. hence, we evaluated allelic variation due to short tandem repeats (strs) in trna gene of e. histolytica and clinical phenotypes of amoebiasis. asymptomatic cyst passers (n=24), patients with dysentery (n=56) and ala (n=107) were included. extracted dna from stool (dysentery, asymptomatic cyst passers) and liver as ...	2014	24495629
a novel c-terminal homologue of aha1 co-chaperone binds to heat shock protein 90 and stimulates its atpase activity in entamoeba histolytica.	cytosolic heat shock protein 90 (hsp90) has been shown to be essential for many infectious pathogens and is considered a potential target for drug development. in this study, we have carried out biochemical characterization of hsp90 from a poorly studied protozoan parasite of clinical importance, entamoeba histolytica. we have shown that entamoeba hsp90 can bind to both atp and its pharmacological inhibitor, 17-aag (17-allylamino-17-demethoxygeldanamycin), with kd values of 365.2 and 10.77 μm, r ...	2014	24486610
insights into the gtp/gdp cycle of rabx3, a novel gtpase from entamoeba histolytica with tandem g-domains.	members of the small gtpase ras superfamily regulate a host of systems through their ability to catalyze the gtp/gdp cycle. all family members reported thus far possess a single gtpase domain with a p-loop containing a nucleoside triphosphate hydrolase fold. here for the first time we report a novel member from entamoeba histolytica, ehrabx3, which harbors two gtpase domains in tandem and exhibits unique biochemical properties. a combination of biochemical and microcalorimetric studies revealed ...	2014	24471929
stress granule formation in entamoeba histolytica: cross-talk between ehmlbp, ehrle3 reverse transcriptase and polyubiquitinated proteins.	the entamoeba histolytica-methylated line-binding protein (ehmlbp) binds to methylated repetitive dna and is a positive regulator of a reverse transcriptase of a long interspersed nucleotide element (line). this protein protects trophozoites against heat shock by reducing protein aggregation. the presence of ehmlbp and polyubiquitinated proteins in heat shock-induced protein aggregates raised the question whether these proteins interact. this assumption was confirmed by co-immunoprecipitation ex ...	2014	24471581
synthesis of 3-tetrazolylmethyl-4h-chromen-4-ones via ugi-azide and biological evaluation against entamoeba histolytica, giardia lamblia and trichomona vaginalis.	the synthesis of novel 3-tetrazolylmethyl-4h-chromen-4-ones via an ugi-azide multicomponent reaction and their biological evaluation against entamoeba histolytica, giardia lamblia and trichomona vaginalis are described. reported yields are moderate to good and biological results show that these compounds could be considered as candidates to anti-parasitic drugs, especially against g. lamblia.	2014	24468633
a genomewide overexpression screen identifies genes involved in the phosphatidylinositol 3-kinase pathway in the human protozoan parasite entamoeba histolytica.	entamoeba histolytica is a protozoan parasite that causes amoebic dysentery and liver abscess. e. histolytica relies on motility, phagocytosis, host cell adhesion, and proteolysis of extracellular matrix for virulence. in eukaryotic cells, these processes are mediated in part by phosphatidylinositol 3-kinase (pi3k) signaling. thus, pi3k may be critical for virulence. we utilized a functional genomics approach to identify genes whose products may operate in the pi3k pathway in e. histolytica. we ...	2014	24442890
nano-yeast-scfv probes on screen-printed gold electrodes for detection of entamoeba histolytica antigens in a biological matrix.	the time and costs associated with monoclonal antibody production limit the potential for portable diagnostic devices to penetrate the market. replacing the antibody with a low-cost alternate affinity reagent would reduce the costs of diagnostic development and use, and lead to new portable diagnostic devices towards many diseases. herein, we present low-cost affinity reagents, nano-yeast-scfv, on commercially available, inexpensive, and portable screen-printed electrodes for the label-free elec ...	2014	24434498
bioassay-guided fractionation of extracts from codiaeum variegatum against entamoeba histolytica discovers compounds that modify expression of ceramide biosynthesis related genes.	leaves of codiaeum variegatum ("garden croton") are used against bloody diarrhoea by local populations in cameroon. this study aims to search for the active components from c. variegatum against entamoeba histolytica, and thereby initiate the study of their mechanism of action. a bioassay-guided screening of the aqueous extracts from c. variegatum leaves and various fractions was carried out against trophozoites of e. histolytica axenic culture. we found that the anti-amoebic activity of extract ...	2014	24416462
amoebicidal activity of essential oil of dysphania ambrosioides (l.) mosyakin & clemants in an amoebic liver abscess hamster model.	amebiasis is a parasitic disease that extends worldwide and is a public health problem in developing countries. metronidazole is the drug recommended in the treatment of amebiasis, but its contralateral effects and lack of continuity of treatment induce low efficiency, coupled with the appearance of resistant amoebic strains. therefore, the search of new compounds with amoebicidal activity is urgent and important. in this study, we evaluated the in vitro and in vivo antiamoebic activity of the e ...	2014	24757495
genital infection caused by entamoeba histolytica confirmed by polymerase chain reaction analyses.	entamoeba histolytica is estimated to infect approximately 1% of the global population. in japan, the prevalence of amebic dysentery has been increasing, with more than 800 patients newly diagnosed annually. however, genital infection with e. histolytica is uncommon even in endemic areas. we present a case of vaginitis caused by e. histolytica. a 50-year-old japanese woman without history of overseas travel presented to a nearby clinic with increased vaginal discharge. she had hemorrhagic erosio ...	2014	24750396
water-soluble ruthenium complexes bearing activity against protozoan parasites.	parasitic illnesses are major causes of human disease and misery worldwide. among them, both amebiasis and chagas disease, caused by the protozoan parasites, entamoeba histolytica and trypanosoma cruzi, are responsible for thousands of annual deaths. the lack of safe and effective chemotherapy and/or the appearance of current drug resistance make the development of novel pharmacological tools for their treatment relevant. in this sense, within the framework of the medicinal inorganic chemistry, ...	2014	24740394
proteomic profiling reveals that ehpc4 transcription factor induces cell migration through up-regulation of the 16-kda actin-binding protein ehabp16 in entamoeba histolytica.	actin cytoskeleton is an essential structure involved in cell migration and invasion in parasites. in entamoeba histolytica, the protozoan parasite causing human amoebiasis, the mechanisms underlying the expression of migration-related genes are poorly understood. here, we investigated the biological effects of ectopic overexpression of ehpc4 (positive coactivator 4) in cell migration of e. histolytica trophozoites. using differential in gel two-dimensional electrophoresis, 33 modulated proteins ...	2014	24721673
naegleria fowleri: contact-dependent secretion of electrondense granules (edg).	the free living amoeba naegleria fowleri is pathogenic to humans but also to other mammalians. these amoebae may invade the nasal mucosa and migrate into the brain causing cerebral hemorrhagic necrosis, a rapidly fatal infection. knowledge of the cytolytic mechanism involved in the destruction of brain tissues by naegleria trophozoites is limited. in other amoebic species, such as entamoeba histolytica, we have previously reported the possible lytic role of small cytoplasmic components endowed w ...	2014	24721258
unusual findings in appendectomy specimens of adults: retrospective analyses of 1466 patients and a review of literature.	diseases and tumors of the appendix vermiformis are very rare, except acute appendicitis.	2014	24719727
trogocytosis by entamoeba histolytica contributes to cell killing and tissue invasion.	entamoeba histolytica is the causative agent of amoebiasis, a potentially fatal diarrhoeal disease in the developing world. the parasite was named "histolytica" for its ability to destroy host tissues, which is probably driven by direct killing of human cells. the mechanism of human cell killing has been unclear, although the accepted model was that the parasites use secreted toxic effectors to kill cells before ingestion. here we report the discovery that amoebae kill by ingesting distinct piec ...	2014	24717428
production of recombinant entamoeba histolytica pyruvate phosphate dikinase and its application in a lateral flow dipstick test for amoebic liver abscess.	amoebic liver abscess (ala) is the most common clinical manifestation of extraintestinal amoebiasis especially in developing countries, causing up to 100 000 fatal cases annually. accurate and early diagnosis is important to prevent the disease complications, however its diagnosis still poses many challenges due to the limitations of the available detection tools. pyruvate phosphate dikinase (ppdk), an excretory-secretory protein of e. histolytica, has been reported as a potential diagnostic mar ...	2014	24708664
the awareness of health professionals in diagnostic techniques for intestinal parasites in gaza strip, palestine.	diagnosis of intestinal parasites still depends on conventional methods in gaza strip hospitals and private laboratories.	2014	24669336
amebic liver abscess: fine needle aspiration diagnosis.	to describe the findings in fine needle aspiration (fna) of an amebic liver abscess (ala).	2014	24662424
parasitic infections of the appendix as a cause of appendectomy in adult patients.	assessment of frequency and clinical findings of parasitic infections for etiology of acute appendicitis.	2014	24659695
noninvasive intestinal amebiasis: entamoeba histolytica colonization without invasion.	entamoeba histolytica infection remains a major cause of morbidity and mortality worldwide. although research with the organism began in the late nineteenth century, our understanding of the natural history of the infection remains incomplete and is heavily based on expert opinion. most persons infected with e. histolytica are carriers with the organism colonizing the large intestine. host defense mechanisms that prevent invasive diseases are poorly understood. a timely review could lead to rene ...	2014	25101557
serological surveillance development for tropical infectious diseases using simultaneous microsphere-based multiplex assays and finite mixture models.	a strategy to combat infectious diseases, including neglected tropical diseases (ntds), will depend on the development of reliable epidemiological surveillance methods. to establish a simple and practical seroprevalence detection system, we developed a microsphere-based multiplex immunoassay system and evaluated utility using samples obtained in kenya.	2014	25078404
regulation of gene expression in the protozoan parasite entamoeba invadens: identification of core promoter elements and promoters with stage-specific expression patterns.	developmental switching between life-cycle stages is a common feature among many pathogenic organisms. entamoeba histolytica is an important human pathogen and is a leading parasitic cause of death globally. during its life cycle, entamoeba converts between cysts (essential for disease transmission) and trophozoites (responsible for tissue invasion). despite being central to its biology, the triggers that are involved in the developmental pathways of this parasite are not well understood. in ord ...	2014	25075445
hypocholesterolemia in patients with an amebic liver abscess.	many parasites induce changes in the lipid profiles of the host. cholesterol increases the virulence of entamoeba histolytica in animal models and in vitro culture. this study aimed to determine, in patients with an amebic liver abscess, the correlation between cholesterol and other features, such as the size and number of abscesses, standard hematological and serum chemistry profiles, liver tests, and duration of hospital stay.	2014	25071907
amoebic anal fistula: new insight into an old disease.	a 67-year-old gentleman underwent fistulectomy for low trans-sphincteric anal fistula along with curettage for an associated abscess extending proximally for half a centimeter into the intersphincteric plane. the roof of the cavity became clearly visible after satisfactory culmination of the surgical procedure. histopathological examination of the fistulous tract and the curetted granulation tissue revealed presence of multiple trophozoites of entamoeba histolytica exhibiting erythrophagocytosis ...	2014	25053686
repurposing the open access malaria box to discover potent inhibitors of toxoplasma gondii and entamoeba histolytica.	toxoplasmosis and amebiasis are important public health concerns worldwide. the drugs currently available to control these diseases have proven limitations. therefore, innovative approaches should be adopted to identify and develop new leads from novel scaffolds exhibiting novel modes of action. in this paper, we describe results from the screening of compounds in the medicines for malaria venture (mmv) open access malaria box in a search for new anti-toxoplasma and anti-entamoeba agents. standa ...	2014	25049259
asymptomatic intestinal amebiasis in japanese hiv-1-infected individuals.	seventy-one asymptomatic human immunodeficiency virus-1 (hiv-1) -infected individuals who underwent colonoscopy for detection of diseases other than amebiasis were included in this study. ulcerative lesions caused by entamoeba histolytica were identified by colonoscopy and biopsy in 11.3% (8 of 71) of individuals. stool microscopic examination hardly identified entamoeba, whereas serum antibody against e. histolytica was often elevated in patients with subclinical intestinal amebiasis. human leu ...	2014	25048374
dna extraction from protozoan oocysts/cysts in feces for diagnostic pcr.	pcr detection of intestinal protozoa is often restrained by a poor dna recovery or by inhibitors present in feces. the need for an extraction protocol that can overcome these obstacles is therefore clear. qiaamp® dna stool mini kit (qiagen) was evaluated for its ability to recover dna from oocysts/cysts directly from feces. twenty-five giardia-positive, 15 cryptosporidium-positive, 15 entamoeba histolytica-positive, and 45 protozoa-free samples were processed as control by microscopy and immunoa ...	2014	25031466
degradation of the transcription factors nf-κb, stat3, and stat5 is involved in entamoeba histolytica-induced cell death in caco-2 colonic epithelial cells.	entamoeba histolytica is a tissue-invasive protozoan parasite causing dysentery in humans. during infection of colonic tissues, amoebic trophozoites are able to kill host cells via apoptosis or necrosis, both of which trigger il-8-mediated acute inflammatory responses. however, the signaling pathways involved in host cell death induced by e. histolytica have not yet been fully defined. in this study, we examined whether calpain plays a role in the cleavage of pro-survival transcription factors d ...	2014	25352693
prevalence of cryptosporidiosis in renal transplant recipients presenting with acute diarrhea at a single center in pakistan.	cryptosporidium is an intracellular protozoan organism which causes diarrhea, both in immunocompetent and immunocompromised hosts. renal transplant recipients are prone to develop a variety of infections including protozoal infections.	2014	25374881
structure-based identification of inositol polyphosphate 1-phosphatase from entamoeba histolytica.	inositol polyphosphate 1-phosphatase from entamoeba histolytica (ehippase) is an mg(2+)-dependent and li(+)-sensitive enzyme that catalyzes the hydrolysis of inositol 1,4-bisphosphate [ins(1,4)p2] into myo-inositol 1-monophosphate and po4(3-). in the present work, ehippase has been biochemically identified and its crystal structure has been determined in the presence of mg(2+) and po4(3-) at 2.5 å resolution. this enzyme was previously classified as a 3'(2'),5'-bisphosphate nucleotidase in the n ...	2014	25372691
mass spectrometric analysis of l-cysteine metabolism: physiological role and fate of l-cysteine in the enteric protozoan parasite entamoeba histolytica.	l-cysteine is essential for virtually all living organisms, from bacteria to higher eukaryotes. besides having a role in the synthesis of virtually all proteins and of taurine, cysteamine, glutathione, and other redox-regulating proteins, l-cysteine has important functions under anaerobic/microaerophilic conditions. in anaerobic or microaerophilic protozoan parasites, such as entamoeba histolytica, l-cysteine has been implicated in growth, attachment, survival, and protection from oxidative stre ...	2014	25370494
bone marrow dendritic cells from mice with an altered microbiota provide interleukin 17a-dependent protection against entamoeba histolytica colitis.	there is an emerging paradigm that the human microbiome is central to many aspects of health and may have a role in preventing enteric infection. entamoeba histolytica is a major cause of amebic diarrhea in developing countries. it colonizes the colon lumen in close proximity to the gut microbiota. interestingly, not all individuals are equally susceptible to e. histolytica infection. therefore, as the microbiota is highly variable within individuals, we sought to determine if a component of the ...	2014	25370489
[the current view of the diagnosis and management of amebiasis in the light of the authors own case reports].	this comprehensive review is focused on a serious protozoan disease, amebiasis. this disease is caused by the human parasite entamoeba histolytica (e. histolytica), the second leading cause of mortality due to protozoan disease worldwide (the leading cause is malaria). the incidence of amebiasis in the czech republic is very low, but it may be underreported as the disease often escapes diagnosis. intestinal colonisation by e. histolytica may be asymptomatic. the clinical picture ranges from diar ...	2014	25412488
duplex microfluidic sers detection of pathogen antigens with nanoyeast single-chain variable fragments.	quantitative and accurate detection of multiple biomarkers would allow for the rapid diagnosis and treatment of diseases induced by pathogens. monoclonal antibodies are standard affinity reagents applied for biomarkers detection; however, their production is expensive and labor-intensive. herein, we report on newly developed nanoyeast single-chain variable fragments (nyscfv) as an attractive alternative to monoclonal antibodies, which offers the unique advantage of a cost-effective production, s ...	2014	25192256